In an existing communications system, a baseband chip and a radio frequency circuit typically need to work in collaboration, where the radio frequency circuit is generally responsible for transmitting or receiving a radio frequency signal, and the baseband chip is generally responsible for performing a series of processing on the radio frequency signal; for example, on a transmitter, the baseband chip may encode an audio signal into a radio frequency signal to be transmitted, and on a receiver, the baseband chip may decode a received radio frequency signal into an audio signal. Moreover, the baseband chip also has a signal processing function, such as encoding/decoding address information, text information, and picture information.
The baseband chip further has an important function, which is performing, by using a series of complex algorithms, processing such as carrier recovery or carrier generation on a signal that passes through a radio frequency circuit, so as to correct an error of a signal, thereby ensuring accuracy of a radio frequency signal that is transmitted/received by the radio frequency circuit. An example is described as follows:
As shown in FIG. 1a, which is a radio frequency circuit architecture in the prior art, a receiver and a transmitter are integrated together and are connected to a same baseband chip, so that the baseband chip performs processing such as carrier recovery or carrier generation on a signal that passes through the receiver and the transmitter. For example, as shown in FIG. 1b, which is a general processing procedure for performing carrier recovery on a signal by a baseband chip, where the baseband chip obtains a phase error according to an error that is obtained by a phase detector by performing detection, and after performing processing according to corresponding algorithms by using a loop filter and a digital oscillator, outputs an error-corrected phase signal.